Duplicating machine



at. 1, 1935. c. E. BOUTWELL DUPLICATING MACHINE Filed Aug. 23, 1952 2 Sheets-Sheet l 1935. c. E. BOUTWELL DUPLICATING MACHINE Filed Aug. 23, 1932 2 Sheets-Sheet 2 INVENTOR.

Patented Oct. 1, 1935 UNITED STATES PATENT OFFICE DUPLICATING MACHINE Clarence Edward Boutwell, Birmingham, Ala. Application August 23, 1932, Serial No. 630,084

7 Claims. (Cl. 101-115) My invention relates to that type of duplicating machine in which a sheet of paper is rolled under a rotary drum upon which are mounted a stencil and, beneath the stencil, an inking pad. Similar machines are in wide use, and it is customary to employ a semi-cylindrical rotary drum with small holes perforating its surface, a single inking pad of absorbent cloth around its outer surface, and a stencil outside of the cloth pad, both pad and stencil being secured to the drum at its longitudinal edges. A sheet of paper is pressed against the stencil, and ink from the pad comes through the stencil making the desired impression upon the paper. This is repeated until the desired number of sheets have been printed. When more ink is needed it is applied to the pad from the inside through the perforations of the drum.

It is often desirable that more than one color of ink be shown on the printed sheet, but the process makes it necessary to use a sticky, slowlyflowing ink, and it has been found difiicult to use two colors of ink upon a single large pad. The squeezing action between the paper, stencil, pad and drum, which forces the ink out through the stencil, also tends to mix together the ink in adja cent portions of the pad. Therefore if two colors of ink are used this soon gives an undesirable blending of colors instead of a sharp demarcation where the two colors are adjacent.

My invention makes it possible to use two or more colors on the same drum, and to print any desired number of impressions without blending of the inks.

Referring to the drawings, Fig. 1 shows in small scale the general arrangement of my machine; Fig. 2 shows in larger scale a partial cross section through the drum, stencil and paper when in operation; Fig. 3 shows in still larger scale a view similar to Fig. 2; Fig. 4 is an elevation of part of the face of the drum with the stencil removed and part of the pads removed; Figs. 5 and 6 are enlarged views of a paper strip and a single wire fastener, respectively; and Fig. '7 is a small scale view of a partially assembled pad.

A frame I carries a semi-cylindrical drum 2 which is held by screws 2 to the ends 2", the whole being revolvable on its axis by means of the handle 3. Below the drum is a roller 4, and a table 5 is so placed that a sheet of paper 6, pushed along the table, enters between 2 and 4. The drum 2 has many round perforations 'I, I and also slotted perforations 8, 8 and 9, 9, covering its entire working surface. Several separate inking pads III-40, II-II, I2, I3, I4, are secured to the drum, and a single stencil I5 is outside of the pads and secured to the drum at its longitudinal edges by pins I'I, I8, or by some other suitable means.

The pads III}, II--II and I2 are strips of absorbent cloth which pass through slots in the drum and are secured inside as by pins I9, I9, or in any other convenient way. The pads I3 and I4 are irregular in shape and the sheet from which they are cut consists of a cloth pad 23 10 which is attached to a flexible perforated sheet of paper 2I, and the small wires 22, 22 are used to secure the pad. to the drum.

Strips of waxed paper 23, 23 separate adjacent pads where they pass through the same slot; and other pieces of T-shaped wax paper 24, 24 are used to separate the pads at other places. Fig.

5 shows some of this T-shaped paper in larger scale. The height of the double part is the same as the thickness of the ink pads, and the single parts are placed flat against the drum. The slots 26, 28 make it easy to bend the paper when desired. Since the Waxed paper is non-absorbent it makes an effective barrier between the two inks and so prevents blending of the different colors.

Fig. 7 shows how the pads I3, I4 are first made up in a large sheet. The paper 2| is perforated in a Way which corresponds with the holes in the drum 2. The wires 22, 22 are placed in position through the perforations, and the curved portion 0 of each wire, shown more clearly in Fig. 6, keeps the projecting ends of the wires steady. The pad 20 is then pressed against the paper 24 and secured thereto by shellac or glue previously coated over 2|. This also secures the wires 22, 22. From the completed sheet are cut out pads of any shape as required by the stencil which is to be used.

Operation is as follows: Assume that a stencil is to be used which requires red ink over the areas I2 and I3, while all other parts are to be printed in black ink. A strip of cloth pad I2 is lifted out of the container in which the red-inked strips are kept, and is placed in position on the drum, being secured by pins I9. Then a pad 83 is cut out of the sheet and secured to the drum by means of the wires 22, 22, as shown in Fig. 3. The irregular piece I4 is similarly cut out and placed, and a piece of waxed paper 24 is placed between I3 and I4 where they are adjacent.

The pad I4 is so cut that while its top edges meet the edges of the pad I3 its lower edges come just to slots in the drum 2. Then black inked strips of cloth pad are taken out of another container and placed at I0-I0, II-I I, thereby covering all the rest of the drum, and waxed paper strips, either '23 or 24, are placed wherever the color of the ink changes. Now ink is applied by brushes to the pads I3 and I4, red to H5 and black to M. The stencil is then placed outside of all the pads, drawn tightly and fastened to the drum at H and 18. Sheets of paper 6. are successively pushed along the table 5, and as the drum is revolved by the handle 3 each sheet is pressed against the stencil, printing it in the well known manner.

It is obvious that the cloth strips and the pieces cut from the pad shown in Fig. 7 can be arranged to give any desired shape of pads which the stencil may require; but since it is often desired to have a bar of differently colored ink extending straight across the printed paper, circumferential slots 9, 9 are also provided so that inking pads of cloth strips like 10 or I2 may be used in such cases.

As the successive sheets of paper are being printed, some ink from each pad tends to work through the perforations and show on the inside of the drum. Therefore, when additional ink is needed on one of the pads, the proper color can be applied to it from the inside of the drum by means of a brush.

I claim:

1. In a duplicating machine, a cylindrically curved, revolvable, perforated drum, a multiplicity of differently colored ink-pads each containing a main supply of ink and secured to the outside of the" drum by means passing through perforations in the drum, a stencil outside of the said ink pads and supported by the drum, together with means to press a sheet against the outside of the stencil.

2. In a duplicating machine, a cylindrically curved, revolvable, perforated drum, a multiplicity of differently colored ink-pads each containing a main supply of ink and secured to the drum by a portion of the pad which passes through a perforation and is secured inside of the drum, a stencil outside of the said ink-pads and supported by the drum, together with means to press a 5 sheet against the outside of the stencil.

3. In a duplicating machine, a cylindrically curved, revolvable, perforated drum, an ink-pad unit'supported on the outside of the drum, a multiplicity of clip members which are a part of 10 the ink-pad unit and which are engagable with perforations in the drum and a stencil outside of the pad and secured to the drum.

4. In a duplicating machine, a cylindrically curved, revolvable, perforated drum, an ink-pad unit and a multiplicity of individual clip meml bers which pass through perforations in the drum and secure the pad to the drum, and a stencil outside of the pad and secured to the drum.

5. In combination with a duplicating machine having a cylindrically curved, revolvable, perfo- 1 rated drum, an ink-pad with a multiplicity of holding members secured thereto, said holding members being spaced to correspond with the perforations in the said drum, and a stencil outside of the pad and secured to the drum.

6. The combination with a duplicating machine having a cylindrically curved, revolvable, perforated drum, of aflexible ink-pad with a multiplicity of holding members secured thereto, said holding members being engagable with perforations in the said drum, and a stencil outside of the pad and secured to the drum.

'7. In a duplicating machine having a rotary drum and differently colored ink-pads outside of the drum and adjacent to one another, an inkbarrier consisting of a piece of treated paper folded into a T shape, and placed outside of the drum and between the said ink-pads.

C. EDWARD BOU'IWELL. 

